rustfmt: update to a newer nightly build (2024-06-23)

This should recognize new rustdoc syntax behaviors.

requested review from @brad.king

Do: reformat --whole-tree

Warnings:

• please consider adding a changelog entry in one of the ghostflow/CHANGELOG.md, ghostflow-cli/CHANGELOG.md, ghostflow-github/CHANGELOG.md, ghostflow-gitlab/CHANGELOG.md files.

The warnings do not need to be fixed, but it is recommended to do so.

This topic is clean and required no reformatting.

Warnings:

• please consider adding a changelog entry in one of the ghostflow/CHANGELOG.md, ghostflow-cli/CHANGELOG.md, ghostflow-github/CHANGELOG.md, ghostflow-gitlab/CHANGELOG.md files.

The warnings do not need to be fixed, but it is recommended to do so.

Combining into !333 (merged) to handle the clippy fixes as well.

closed